Radiator



Jan. 19, 1932. *F. K. HOFFMAN RADIATOR .Filed April 19, 1930 Patented Jan. 19, 1932- UNITED STATES PATENT. OFFICE RADIATOR Application filed April 19, 1930. Serial No. 445,739.

This invention relates to radiators, and more particularly to a radiating or heat exchange element that is produced 1n tubular form, such element being adapted either to be assembled in multiplewith suitable headers to constitute a radiator unit for varlous and general uses, or the improved tubular radiating element may be employed without headers and extended to any extent 118065891X for any required heat exchange purpose. principal object of the invention is to provide a tubular radiator element of integral construction equipped with integral radiating fins or ribs spaced apart along the length thereof, such fins being solid and relatively massive and strong, though integral with the body of the tube. In accordance with my invention my improved tubular radiating element is produced preferably by rolling or spinning action, so that the metal of these radiating fins is condensed and the tubular radiating structure as a whole made strong and capable of withstanding great pressures and severe usage. A further object is to provide a tubular radiating element providlng a relatively large surface area for radiation in a structure that is light in weight and easily handled and installed. A still further object is to provide a tubular radiator element of the kind described, that is constituted to absorb Within itself any degree of heat expansion and contraction to which it, or the radiator as a whole may be subjected.

The foregoing and other objects and advantages of the invention will be better understood from the following detailed description taken in connection with the accompanying drawings and the distinctive features of novelty will be thereafter pointed out in the appended claims.

Referring to the drawings;

Figure 1 is an elevation with an intermediate portion broken away, and another part in central longitudinal section of a radiato element embodying my invention.

Figure 2 is an end view thereof.

Figure 3 is a transverse section on line 33 of Figure 1, and.

Figure4 is a plan view, with an intermediate portion broken away, of a radiator unit with the tubular radiating element of my invention assembled in multiple therein, a portion of one of the headers being broken away.

10 indicates a tubular structure embodying the principles of my invention. This comprises a tube of any suitable ductless metal such as aluminum, copper, or the like. In producing the radiator element of my invention, this tube is subjected to a rolling or spinning action preferably between oppositely co-acting rolls, which operate to produce a series of spaced apart radial fins or ribs 11 with intermediate hollows or valleys 12 between'such ribs. The height of these ribs and the depth of the intermediate valleys may be increased or decreased at will according to the requirements of any particular type of radiator to be produced by a variable setting of the rolling machine mechanism as will be readily understood. The invention contemplates, however, that the height of these fins shall be substantially greater than the width thereof.

It will be noted that the fins or ribs 11- are in the major portion thereof solid and relatively thick and massive as compared with the thickness of the intermediate metal therebetween, and further that the hollowof the tube extends up into the bases of these fins to a substantial extent as indicated at 13. Thus is produced a tubular structure which introduces the fluid within the tubes Well up into the bases of the fins so that they are adapted to carry out their radiating function to the best advanta e while the fins themselves are strong and durable providing great resistance against fluid pressure and also protecting the structure against rough usage.

It will be noted that by the described struc-, ture, the radiating surface of the tubular element is greatly increased, in practice a tube having a radiating area of 100 square inches being increased to as much as 250 square inches by its transformation into the described structure. It is to be also noted that the formation of the valleys 12 between the fins is such as to permit ready expansion and contraction of the entire element lengthwise to any extent that may be necessary in use, also that the integrally formed fins are not only more effective for radiation purposes by reason of the bringing into the interior fiuid out into the base of the fin, but also there are no dead air pockets in or between the fins as is the case where radiating fins or ribs are slipped on to radiator tubes as separate elements. The integral structure described has the still further advantage that there is never an whistling of the fins by air as is apt to be t e case with separately formed fins.

It will be evident that my improved radiating or heat transfer element is relatively very light in proportion to its radiating capacity, and that it is susceptible of easy and convenient installation. In Figure 4 I show a series of my improved radiating elements 10 assembled with suitable headers 14, 15. For this purpose I may form the end portions of the tubular elements with a reduced collar extremity 16 and with the first fin 11a somewhat out down to receive a suitable assembling nut or sleeve (not shown) by which it may be secured in an extendin boss 17 of the header. It will be understood that my improved radiator element may be produced in any suitable length, and that it may either be assembled with header elements as shown to constitute a radiator unit, or it may be extended as much as necessary and used, either coiled up or otherwise without headers, such as for heat transfer purposes in stills and the like.

I am aware that the invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and I therefore desire the present embodiment to be considered in all respects as illustrated and not restrictive, reference being had to the appended claims rather than to the foregoing description to indicate the scope of the invention. 4

Having now described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A tubular radiating element having a series of spaced apart rolled fins along the length thereof with the interior opening of said element extending outward into the bases of said fins, said fins being relatively thick and massive as compared with the intermediate material of said element, and the height thereof being substantially greater than the width thereof.

2. A tubular radiating element equipped with a series of spaced apart fins along the length thereof and integral therewith with the hollow interior of said element extending outward into the bases of said fins, and with the intermediate portions of said element between said fins substantially concaved to permit endwise expansion and contraction of said element, the hei ht of said fins bein substantially greater t an the width thereo 3. A tubular radiating element having in- 

